Formation-sampling apparatus



Aug. 25, 1970 Filed Oct. 7, 1968 H. J. URBANOSKY FORMATION-SAMPLING APPARATUS 2 Sheets-Sheet l ffw INVENTQR.

Aug' 25 1970 H. J. uRBANosKY 3,525,407

FORMATION-SAMPLING APPARATUS 2 Sheets-Sheet 2 Filed OCI'.. '7, 1968 INVENTOR. M

United States Patent Office 3,525,407 Patented Aug. 25, 1970 3,525,407 FORMATION-SAMPLING APPARATUS Harold J. Urbanosky, Houston, Tex., assignor to Schlumberger Technology Corporation, New York, N.Y., a

corporation of Texas Filed Oct. 7, 1968, Ser. No. 765,383 Int. Cl. E21b 49/06 U.S. Cl. 175-78 19 Claims ABSTRACT F THE DISCLOSURE The particular embodiment described herein as illustrative of the invention is directed to formation-sampling apparatus for successively collecting and segregating a plurality of samples from earth formations traversed by a borehole. To accomplish this, the disclosed borehole apparatus includes selectively-operable means adapted for successively collecting samples from the exposed faces of selected earth formations. During each operation of the sample-collecting means, the collected formation sample is deposited in a sample receiver on the apparatus and selectively segregated from other samples.

At present, multiple formation samples are usually obtained from previously-drilled boreholes by explosively propelling into the adjacent wall of a borehole one or more so-called core-taking bullets having appropriately arranged forward cutting edges. As these tubular bullets penetrate the borehole wall, a generally-cylindrical core of the exposed formation materials is usually driven into each bullet so that, when the bullets are subsequently retrieved, these cores can be recovered at the surface for examination. Although such core-taking bullets have been highly successful, the samples obtained thereby are from spaced intervals along the borehole. It is apparent, of course, that the most ideal arrangement is to obtain in a single trip continuous samples of considerable length from all formation intervals of interest in a given borehole. Heretofore, however, this has not been commercially feasible at least from boreholes that have been previously drilled.

One tool as shown in Pat. No. 3,173,500 has been proposed, however, in which a pair of rotatable outwardlyconverging cutting wheels are cooperatively arranged to be extended outwardly and cut their Way into an adjacent formation. Then, as they are slowly raised, the cutting wheels cut a single elongated wedge-shaped formation sample out of the borehole wall. This individual sample is caught by the tool and returned to the surface. It will be appreciated, of course, that a tool such as this would be far more eicient if a number of such samples could be obtained on a single trip into a borehole so long as these samples can be accurately identified later.

Accordingly, it is an object of the present invention to provide new and improved formation-sampling apparatus for successively collecting a plurality of formation samples from selected positions in a borehole and reliably segregating these samples from one another for later identification.

This and other objects of the present invention are attained by providing formation-sampling apparatus with means adapted for selectively collecting samples from one or more selected earth formations and a receiver adapted to contain these samples. To segregate the samples as they are collected, the formation-sampling apparatus further includes one or more dividers that, in response to successive operations of the apparatus, are selectively interposed between the samples as they are received to insure that the individual samples are not commingled with one another.

The novel features of the present invention are set forth with particularity in the appended claims. The invention, together with further objects and advantages thereof, may be best understood by way of the following description of exemplary apparatus employing the principles of the invention as illustrated in the accompanying drawings, in which:

FIG. l depicts an exemplary formation-sampling tool arranged in accordance with the present invention and in position in a borehole to obtain one of several formation samples;

FIG. 2 is a schematic representation of the formationcollecting means of the tool shown in FIG. l;

FIG. 3 is a somewhat simplified, cross-sectioned elevational view of the sample receiver of the exemplary tool shown in FIG. 1;

FIG. 4 is an elevational view, partially in cross-section, of the upper and lower ends of the sample receiver shown in FIG. 3;

FIG. 5 is a cross-sectional view taken along the lines 5--5 in FIG. 4; and

FIG. 6 is a developed view of the surface of one of the elements Idepicted in FIG. 4.

Turning now to FIG. 1, a formation-sampling tool 10 arranged in accordance with the present invention and conveniently arranged as a number of tandemly-connected housings 11-14 is shown suspended from a cable 15 in a borehole 16 and in position for formation-collecting means, such as a pair of converging similar cutting wheels 17, that are selectively movable from the surface to remove an elongated sample 18 from the exposed face of an earth formation 19 and deposit it within a sample receiver in the lowermost housing 14.

The upper housing 11 preferably encloses suitable circuitry (such as that described in a copending application, Ser. No. 649,978 led June 29, 1967) for locating the tool 10 at a ydesired position in the borehole 16 as well as for selectively controlling the tool from the surface by Way of various electrical conductors in the suspension cable 15. The next-lower housing 12 preferably includes a pair of hydraulically-actuated pistons 20 for selectively extending a wall-engaging anchor 2l on the rear of the tool 10 laterally against one side of the borehole 16 and shifting the forward face of the sampling tool in the opposite direction. To selectively actuate the wall-engaging member 21 from the surface, a hydraulic pump 22 in the housing 12 is arranged to selectively pump hydraulic fluid into piston chambers either behind or ahead of the pistons 20. By maintaining an increased hydraulic pressure behind the pistons 20, the anchor 21 will, of course, urge the forward face of the tool 10 against the opposite wall of the borehole 16 with suicient force to anchor the tool in a selected position.

The next-lower housing 13 of the tool 10 encloses the cutting wheels 17 that are preferably mounted in converging vertical planes and, as more fully described in a copending application Ser. No. 649,952 led June 29, 1967, now Pat. No. 3,430,717 are arranged to be rotatively driven about outwardly-diverging axes lying generally in the same horizontal plane. The cutting wheels 17 are suitably arranged relative to one another so that, when extended, their peripheral edges will project through a longitudinal opening 23 in the forward wall of the housing 13 and all but come together at about the point of intersection of the three aforementioned planes. Thus, by selectively moving the rotating wheels 17 upwardly, the generally wedge-shaped or triangular prismatic sample 18 will be cut from the adjacent formation 19.

The lowermost housing 14 of the tool 10 is arranged as a receiver for a selected number of formation samples and, as will be subsequently explained, includes means for reliably segregating these samples from one another. In general, the sample receiver 14 is arranged in such a manner that a plurality of dividers therein (not shown in FIG. l) are sequentially positioned to respectively isolate successively-collected formation samples as the tool is operated. In this Imanner, the tool 10 can be efficiently employed on a single trip in the borehole 16 to recover several formation samples that will be individually deposited in the sample receiver 14 in predetermined positions.

Turning now to FIG. 2, the cutting wheels 17 are operatively carried by a longitudinally-movable enclosure 24 having a pair of longitudinal tubular members 25 (only one seen in FIG. 2) along its rear wall and slidably disposed about substantially longer, paralleled longitudinal rods 26 (only one seen in FIG. 2) secured only at their upper and lower ends along the rear wall of the tool housing 13. The opposite ends of these tubular members 25 are slidably sealed around the elongated rods 26 and a piston member 27 (only one seen in FIG. 2) is fixed at an intermediate position on each of the elongated rods 26 to define separate upper and lower uidtight chambers 28 and 29 within the internal bore of its associated tubular member.

Accordingly, by developing a higher fluid pressure in the upper hydraulic chambers 28 than that in the lower hydraulic chambers 29, the tubular members 25 and enclosure 24 secured thereto will be moved longitudinally upwardly along the elongated rods 26 in relation to the stationary tool housing 13. Similarly, by imposing a higher pressure in the lower hydraulic chambers 29 than that in the upper hydraulic chambers 28, the enclosure 24 will travel longitudinally downwardly along the rods 26. A suitable hydraulic pump 30 is mounted within the enclosure 24 and connected by fluid lines 31 and 32 to the hydraulic chambers 28 and 29 so that the pump can be selectively operated from the surface to accomplish the desired travel of the enclosure 24 back and forth along the elongated rods 26.

By arranging a typical bellows or piston (neither shown) at a convenient point in a wall of the enclosure 24, the hydraulic fluid in the enclosure and hydraulic chambers 28 and 29 will be maintained at a pressure at least equal to the hydrostatic pressure of fluids or socalled mud in the borehole 16. In this manner, by pressure balancing the hydraulic system in relation to the borehole hydrostatic pressure, the hydraulic pump 30 needs only to develop a pressure sufiicient to overcome the weight of the enclosure and whatever friction that may be encountered in moving the cutting wheels 17 and the enclosure 24.

To power the cutting wheels 17, an electric motor 33 is fitted into the enclosure 24 and operatively connected by suitable power-transmission means to a right-angle gear drive 34 having outwardly-diverging shafts (as at 35) at an angle to one another for rotatively driving the cutting wheels. By locating the cutting wheel motor 33 in the enclosure 24, it will also be pressure balanced in the same manner as the pump 30. Similarly, as shown in the last-mentioned application, by enclosing the powertransmission means in an oil-filled tube (not seen in FIG. 2) coupled between the enclosure 24 and gear drive 34, the power-transmission rneans and gear drive will also be completely pressure balanced.

A pair of paralleled arms, as at 36, are pivotally connected at their upper ends to the motor enclosure 24 so as to pivot about a generally-horizontal axis and carry the gear drive 34 secured to their lower ends inwardly and outwardly. outwardly-biased pins 37 (only one seen in FIG. 2) mounted near the lower ends of each of the pivoted arms 36 are slidably disposed in a system of grooves (only one system seen in FIG. 2) in the interior side walls of the intermediate housing 13 on opposite sides of the longitudinal opening 23 therein. These groove systems are preferably arranged so that upward longitudinal travel of the motor enclosure 24 from its fullline position to its dashed-line position shown in FIG. 2 will be effective (through the coaction of the guide pins 37 in their respective groove systems) to direct the cutting wheels 17 and gear drive 34 along the path A-B- C-D schematically depicted in FIG. 2. Then, upon downward travel of the enclosure 24 back to its full-line position shown in FIG. 2, the guide pins 37 will return the cutting wheels 17 and gear drive 34 in the opposite direction to their initial positions.

As seen in FIG. 2, the groove systems each have two parallel longitudinal grooves 38 and 39 of unequal length and spaced apart from one another. The shorter forwardmost grooves 38 are connected at their opposite ends to the longer grooves 39 by oppositely-directed rearwardlyinclined grooves 40 and 41 which respectively intersect the longer grooves at longitudinally-spaced intermediate points. To further stabilize the motor enclosure 24 as it moves between its longitudinally-spaced positions, outwardly-directed guides, as at 42 and 43, are respectively mounted on the upper and lower ends of the motor enclosure and slidably confined in the longer longitudinal grooves 39.

Accordingly, as the cutting wheels 17 move along the path A-B, they will be moving upwardly and outwardly as they cut their way into the formation 19. Then, as the rotating cutting wheels 17 move upwardly from their position at B to their position at C, they will be cutting along a straight path of a length determined by the vertical height of the shorter grooves 38. After reaching their positions at C, the cutting wheels 17 will be retracted as they move further upwardly and cut their way toward their position at D. Thus, once the converging cutting wheels 17 have reached the upper position at D, a prismatic sample, as at 18, with tapered ends will have been cut out of the formation 19 for deposit in the core receiver 14 therebelow.

To divert the guide pins 37 into the lower inclined grooves 40 as the enclosure 24 moves upwardly, an abutment 44 is provided across the lower portion of each of the longer grooves 39, with the lower faces of these abutments being extended along the line of the downwardly-facing Wall of the lower inclined grooves 40 to facilitate the redirection of the guide pins. Similarly, when the enclosure 24 has reached its uppermost position (as shown in dashed lines in FIG. 2), it is preferred that the guide pins 37 re-enter the upper grooves 41 so that the cutting wheels 17 will return to their initial position at A by passing back through their respective kerfs which they previously cut into the formation 19. In this manner, the return travel of the cutting wheels 17 will be effective to dislodge the formation sample should it Still be iu the complementary cavity cut in the formation 19. Thus, an abutment 45 (similar to those at 44) is located across each of the longer longitudinal grooves/- 39, with the upper faces of these abutments being a continuation of the lower side Walls of the upper inclined grooves 41. The height of each abutment 44 and 45 is made less than the total depth of its associated inclined groove so that the shorter enclosure guides `42 and 43 can pass freely up and down the longitudinal groove 39 without striking the abutments. Thus, as the springbiased guide pins 37 reach the abrupt faces of the abutments 44 and 45, the cutting wheels 17 will be directed outwardly as desired.

Turning now to FIG. 3, an overall view is shown of a preferred embodiment of the sample receiver 14, with various details thereof being further illustrated in FIGS. 4-6. In general, the sample receiver 14 is selectively operated upon each cyclical movement or operation of the cutting wheels 17 to receive the successively-collected formation samples and to segregate these samples from one another. To accomplish this, the sample receiver 14 includes means such as a plurality of upright transverse dividers 46-48 that are enclosed in the housing and adapted to be selectively moved between transversely-spaced vertical side walls 49 and 50 into predetermined positions for isolating the formation samples as they are successively deposited through the open upper end of the receiver. Motion-responsive means 51 are arranged for selectively positioning the sample-isolating dividers 46-48 in response to the successive cyclical movements of the motor enclosure 24 between its lower and upper positions.

As best seen in FIG. 4, in their preferred form, the dividers 46-48 are fiat, elongated and fairly-limber strips of metal extending longitudinally substantially the full length of the sample receiver 14. Although the lower ends of the transverse dividers 46-48 are preferably spaced at approximately equal intervals between the front and rear walls of the receiver 14, initially at least the upper portions of the dividers are laid along the rear wall of the housing adjacent to one another and retained in this position by the selectively-operable releasing means S1. Thus, with the dividers 46-48 in their initial positions illustrated in FIG. 4, when the first of a number of formation samples is cut away by the cutting wheels 17, it will fall freely through the housing opening 23 into the receiver 14 and come to rest on the forward face of the divider 46. As will shortly be explained in greater detail, the next operation of the formation-sampling tool will be effective to release the divider 46 and allow it to move laterally or forwardly to the generally-upright position illustrated in FIG. 3. Similarly, upon consecutive cyclical operations of the tool 10, the other dividers 47 and 48 Iwill be successively released and moved forwardly to their respective upright positions as shown in FIG. 3.

Although the dividers 46-48 could be made sufficiently resilient to spring forwardly without assistance to their upright positions when released, it is preferred to provide biasing means, such as a number of springs as at 52, for positively shifting the dividers. The springs 52 are either formed in a U with an intermediate transverse portion and its opposite ends coiled or they are formed in an L with one end coiled and a free transverse portion. In either case, the coiled ends of the springs 52 are respectively carried on lateral shafts 53 mounted on the side walls 49 and 50. It will, of course, be appreciated from FIG. 4 that by respectively disposing the intermediate or transverse portions of the springs 52 behind the rear faces of the dividers 4658, upon release of each divider its associated biasing spring or springs will carry the upper end of this divider forwardly to the upright position shown in FIG. 3. To obtain forward movement of the dividers 46-48, it is preferred to support the lower ends of the dividers in spaced notches, as at 54, formed transversely across the upper face of the bottom closure 55 of the housing 14. It will be realized, of course, that for all practical purposes, the movements of the dividers 46-48 will still be substantially lateral.

Referring now to FIGS. 4 and 5, in the preferred embodiment of the selectively-operable releasing means 5.1, a somewhat U-shaped latch 56 is arranged for controlled vertical travel adjacent to the rear wall of the receiver housing 14. Inwardly-turned fingers, as at 57, on the latch 56 are suitably arranged to partially encircle the dividers 46-48 and initially contact the forward face of the divider 46 so long as the latch is in its lowermost position (as depicted in FIG. 4) for retaining the dividers against the rear wall of the receiver 14. The upper ends of the dividers 46-48 are respectively either notched or reduced in width, as at 58-60, so that, as the U-shaped latch 56 is moved upwardly and reaches these notches, the springs 52 will freely shift the reduced or notched upper ends of the dividers forwardly between the opposed fingers 57. To individually release the dividers 46-48 at Selected intervals, the notches 58-60 are located at progressively-higher positions, with the notch 58 on the forwardmost divider 46 being the lowest of the group. Thus, although upward travel of the latch 56 will be effective to release the dividers 46-48, only one divider at a time will be released and the other dividers will be retained against the rear wall of the receiver 14 until the latch has been shifted further upwardly.

In the preferred manner of controlling the longitudinal travel 0f the latch 56, the selectively-operable releasing means 51 further include a cam member such as a vertical spindle shaft 61 that is journaled between longitudinally-spaced bearings 62 and 63 mounted on the rear wall of the housing 14 just below the latch. A somewhatresilient, depending cam follower 64 secured to the latch 56 is extended downwardly alongside the cam spindle and provided with an inwardly-directed cam pin 65 on its lower end that is cooperatively guided by means such as alternating cam grooves 66 formed on the exterior of the rotatable spindle 61 and providing progressivelyhigher cam stops at selected positions thereon. As an alternate, the depending member 64 can be made relatively inflexible and a spring-biased pin substituted for the terminal 65.

As best seen in the developed view depicted in FIG. 6, the system of cam-guiding grooves 66 formed around the spindle 61 includes a plurality of circumferentiallyspaced longitudinal grooves 6770 having at least their upper ends located at progressively-higher positions on the vertical spindle and a plurality of downwardly-inclined grooves 71-74 that respectively interconnect the upper end of one longitudinal groove to the lower end of the next-adjacent higher longitudinal groove. In this manner, the alternated cam-guiding grooves 66 define a circuitous but continuous path around the spindle 61 that begins at the longitudinal groove 67 and progressively moves upwardly to the longitudinal groove 70, with the final inclined groove 74 providing a return path extending downwardly from the upper end of the uppermost longitudinal groove back around the cam spindle to the lower end of the lowermost longitudinal groove.

It will be appreciated, therefore, that for the cam pin 65 to progressively move through the circuitous path defined by the system of cam-guiding grooves 66, the depending cammed member 64 must be alternately moved upwardly and downwardly, with the number of these reciprocating movements being governed by the number of the grooves 67-74. For example, to move the cam pin 65 from the first longitudinal groove 67 to the second longitudinal groove 68, an upward movement of the cam follower 64 is required to carry the pin to the top of the first groove. Then, a downward movement of the cam follower 64 is necessary to shift the finger 65 downwardly through the inclined groove 71 to the bottom of the second longitudinal groove 68. It will be realized, of course, that downward travel of the cam finger 65 along the inclined groove 71 will partially rotate the spindle 61 so as to bring the next effective longitudinal groove 68 into alignment with the reciprocating cam follower 64 and pin or finger 65.

Means must, of course, be provided to insure that downward reciprocating movements of the cam follower 64 will always direct the cam finger 65 into the adjoining inclined groove rather than misdirecting it back down the same longitudinal groove from which the cam pin had previously moved upwardly. In one manner of accomplishing this, the bottoms of the inclined grooves 71-74 are formed at a constant depth and the bottoms of the longitudinal grooves 67-70 are inclined upwardly and outwardly so that their lower ends are somewhat deeper than the inclined grooves and their upper ends are somewhat shallower than the inclined grooves. In this manner, an upwardly-directed shoulder, as at 75, is formed across the upper portion of each longitudinal groove. By making these upwardly-directed shoulders, as at 75, a continuation of the lower wall of the adjoining inclined groove, as at 72, once the cam pin 65 has moved upwardly through the groove 68 into the inclined groove 72, the subsequent downward movement of the reciprocating cam follower 64 can only direct the finger downwardly through the inclined groove since the shoulder 75 blocks the re-entry of the spring-biased cam finger into the longitudinal groove 68. Similarly, these variable depths of the groove system 66 results in longitudinal shoulders, as at 76, being formed across the lower end of each of the inclined grooves 7174 which prevent upward movements of the cam follower 64 from inadvertently carrying the cam finger 65 back into the adjacent inclined groove.

It will be appreciated, therefore, that successive reciprocating movements of the cammed member 64 will be effective to progressively shift the cam finger 65 through the groove system 66, with each upward movement of the depending member being halted with the member at a successively higher elevation as determined by the cam stops cooperatively defined by the upper ends of the longitudinal grooves 67-70. Accordingly, by properly arranging the divider notches 58-60 to correspond with the groove system 66, these reciprocating movements of the depending cammed member 64 will progressively shift the latch 56 higher to accomplish the previouslydescribed sequential releases of the dividers 46-48 as the latch is successively raised above the notches in each by the cyclical operations of the sample-collecting means 17.

To selectively actuate the releasing means 51, an upright tubular member 77 is secured to the latch 56 and the upper end of the depending cammed member 64 and preferably passed upwardly through a guide 78 on the rear wall of the receiver 19. A depending actuator rod 79 is secured to the lower end of the motor enclosure 24 (FIG. 2) and appropriately arranged to be releasably coupled to the upper end of the upright tubular actuating member 77 whenever the enclosure is in the lower portion of its span of travel. In the preferred manner of accomplishing the releasable coupling of the actuator rod 79 and cam-actuating member 78, the lower end of the rod is enlarged, as at 80, and this enlarged head is adapted to be received by a plurality of yieldable collet fingers, as at 81, on the upper end of the tubular actuating member.

Accordingly, in the initial position of the tool 10 where the motor enclosure 24 is at the bottom of its vertical span of travel and the cam pin 65 is at the bottom of the lower longitudinal groove 67, the enlarged rod head 80 will be releasably coupled to the actuating member 78 by the collet fingers 81. Thus, as the enclosure 24 is moved upwardly to cut away the first of a number of formation samples as at 18, the initial upward travel of the enclosure and cutting wheels 17 will be effective to pull the actuating member 78, latch 56, and depending cam-guided member 64 upwardly until the cam pin 65 has reached the first cam stop as defined by the top of the longitudinal groove 67. Once the cam pin 65 reaches this position, the latch 56 will be halted and the continued upward travel of the enclosure 24 will pull the enlarged rod head 80 out of the yieldable collet fingers 81. Friction will retain the latch 56 in its elevated position. It will be noted that at this point the latch 56 Will still be below the notch 58 so that the dividers 46-48 will still be retained in their initial positions.

As previously described, the continued upward travel of the motor enclosure 24 and cutting wheels 17 will cut away the formation sample 18. Thus, at some point during the first cycle of upward and downward travel of the cutting wheels 17, the formation sample 18 will be freed and will fall through the housing opening 23 into the receiver 14 and come to rest on the forward face of the first divider 46. Then, as the downwardly-moving motor enclosure 24 nears the end of its initial cyclical movement, the enlarged head 80 of the actuator rod 79 will again contact the collet fingers 81 and be effective to push the actuating member 78 downwardly until it is halted by the cam pin reaching the bottom of the second longitudinal groove 68. It will be appreciated, of course, that once the tubular member 78 is halted, continued downward travel of the motor enclosure 24 will recouple the enlarged rod head to the collet fingers 81.

Once the first formation sample 18 is in the receiver 14, the first divider 46 must, of course, be released to allow sufficient clearance in the receiver for the entrance of a second formation sample. Accordingly, once the tool 10= is in readiness to collet a second sample, the second upward travel of the cutting wheels 17 will carry the cam pin 65 to the upper end of the groove 68, with the latch 56 passing the divider notch 58 during this movement to release the first divider 46. Thus, during this second cyclical operation of the sample-collecting means 17, the divider 46 will be shifted forwardly by its associated spring 52 to allow a second formation sample (as at 82 in FIG. 3) to fall into the space now opened between the first divider 46 and the second divider 47.

Here again, as the enclosure 24 nears the end of its second downward movement, the cam pin 65 will be shifted into the lower end of the groove 69 and the actuator rod 79 will again be recoupled to the actuating member 78. It will be appreciated that although the actuating member 78 progressively moves upwardly, the actuator rod 79 will merely be shifted further downwardly into the tubular member and does not ever reach either the latch S6 or the depending member 64.

In a similar fashion, the third upward travel of the cutting wheels 17 to cut a third sample (as at 83 in FIG. 3) will elevate the latch 56 above the notch 59 in the divided 47 to release it and make room in the receiver 14 for this third sample. Similarly, as the cutting wheels 17 move up-wardly to cut a fourth sample (as at 84 in FIG. 3), the latch 56 will finally be moved above the notch 60 in the divider 48 and release it to allow this fourth sample to freely enter the receiver 14.

It will be noted in FIG. 3 that, once the dividers 46-48 are released, their upper portions are bowed slightly forwardly over the upper ends of the samples 18 and 82-84. Thus, by making the lim'ber dividers 46-48 somewhat longer than the maximum length of the formation samples 18 and 82-84, the biasing springs 52 will be effective to curve the upper end of each divider over each sample to reliably trap the samples. Furthermore, when, for eX- ample, the first divider 46 has enclosed the first sample 18, the rear face of the forwardly-curved upper end of the divided will provide a convenient incline or ramp for facilitating the subsequent admission of the second sample 82 into the enlarged space now opened between the dividers 46 and 47.

In addition to guiding subsequently-collected formation samples into the reeciver 14, the flexible dividers 46-48 are further effective to facilitate the movement of each sample downwardly until it cornes to rest on a forwardly-projecting step, as at 85, at the lower end of each divider. By way of illustration, it will be appreciated that as the divider 46 is moved forwardly by its associated spring 52, to enclose the sample 18, well bore fiuids in the receiver 14 ahead of the moving divider and between the opposed side walls 49 and -S will be displaced rearwardly around the longitudinal edges of the divider. Thus, since the spring 52 will quickly move the upper end of the divider 46 against the forward wall of the receiver 14, the divider will be temporarily exed and leave a momentary bulge in its intermediate portion. Then, the induced spring force of the flexed divider 46 will gradually straighten the divider progressively downwardly as well bore fluids trapped therebelow escape to the rear of the divider. As this momentary bulge progressively moves downwardly, the passage of the trapped formation sample 18 will, therefore, be greatly facilitated as it falls freely through this enlarged space into its iinal position on the step 85. A corresponding action will, of course, be obtained as the dividers 47 and 48 are successively re leased.

To facilitate the removal of the dividers 46-48 and segregated formation samples, a pin 86 is passed through the lowermost ends of the dividers and releasably secured to the receiver housing 14. Although the dividers 46-48 can be pulled out of the upper end of the receiver 14 once it is uncoupled from the remainder of the tool and the pin 86 is removed, it is preferred to provide a removablev closure 87 in the forward wall of the housing. Thus, when the tool 10 is returned to the surface, the segregated samples 18 and 82-84 can -be readily removed by lifting the dividers 46-48 out of the housing 14.

Accordingly, it will be appreciated that the present invention has provided new and improved formation-sampling apparatus for successively collecting and segregating samples from earth formations traversed by a borehole. Although changes and modifications may be made in the disclosed embodiment without departing from the broad principles of the invention, by providing selectively-positionable dividers in the sample receiver that are successively movable to predetermined positions, as a formation sample is deposited into the receiver each sample will be carefully segregated. Moreover, since the positioning of these dividers is responsive to the successive cyclical operations of the sampling tool, the subsequent identification of the order of taking of segregated samples will be reliably established.

What is claimed is:

1. Formation-sampling apparatus for obtaining samples of earth formations traversed by a borehole and comprising: sample-collecting means adapted for suspension in a borehole and selectively operable from the surface for obtaining samples of earth formations adjacent thereto; a sample receiver having spaced side walls and adapted for containing formation samples obtained by said sample-collecting means; a transverse divider having opposite faces and disposed in said sample receiver for substantially lateral movement therein between two of said side walls; and means operatively positioning said divider initially adjacent to one of said two side walls to direct such formation samples along one face of said divider into one portion of said sample receiver and operative, in response to a predetermined operation of said sample-collecting means, for repositioning said divider adjacent to the other of said two side walls to subsequently direct such formation samples along the other face of said divider into another portion of said sample receiver.

2. The formation-sampling apparatus of claim 1 wherein said divider-positioning means include: means releasably retaining said divider adjacent to said one side wall, and means operatively coupling said retaining means to said sample-collecting means and responsive to said predetermined operation thereof for releasing said divider for movement toward said other side wall.

3. The formation-sampling apparatus of claim 1 wherein said sample-collecting means are adapted for obtaining elongated samples of earth formations; and said receiver is adapted to contain such elongated formation samples in a generally-upright position therein.

4. The formation-sampling apparatus of claim 3 wherein said divider is an elongated member disposed uprightly in said sample receiver for dividing said sample receiver into vertical compartments respectively adapted to c011- tain such upright elongated formation samples; and said divider-positioning means include a latch member releasably retaining said divider adjacent to said one side wall, and means operatively coupling said latch member to said sample-collecting means and responsive to said predetermined operation thereof for releasing said latch member from said divider for repositioning of said divider adjacent to said other side wall.

5. The formation-sampling apparatus of claim 3 wherein said divider includes an extended yieldable upright portion; and said divider-positioning means include spring means, operative upon release of said divider, for deflecting said yieldable portion of said divider further toward said other side wall to at least partially cover said one portion of said sample receiver.

6. Formation-sampling apparatus for obtaining samples of earth formations traversed by a borehole and comprising: a support adapted for suspension in a borehole; formation-cutting means movably mounted on said support and selectively movable from the surface between longitudinally-spaced positions on said support for successively cutting away elongated samples from earth formations adjacent thereto; a sample receiver dependently coupled below said support having an upper openingr adapted for admitting such elongated formation samples as they are successively removed and opposed side walls spaced sufficiently for containing such elongated formation samples admitted therein side-by-side in an upright position; sample-segregating means adapted for isolating such elongated formation samples from one another including an elongated transverse divider movably disposed in said sample receiver in a generally-upright position for vertically dividing said sample receiver and adapted for substantially lateral movement therein between said side walls; first means for selectively positioning said divider adjacent to one of said side walls to define a iirst vertical compartment in said sample receiver between said divider and another of said side walls; and second means cooperable with said first means and operative only upon a predetermined movement of said formation-cutting means for selectively repositioning said divider adjacent to said other side "wall to define a second vertical compartment in said sample receiver between said divider and said one side wall.

.7. The formation-sampling means of claim 6 wherein said formationcutting means are adapted to be cyclically reciprocated between said longitudinally-spaced positions for the collection of each of such elongated samples; and saldl second means are operative only after said formationcutting means complete the rst of such cyclical reciprocations so that the rst of such formation samples will be contained in said tirst vertical compartment and the second of such formation samples will be contained in said second vertical compartment.

8. The formation-sampling apparatus of claim 7 where- 1n said Iirst means include a movable latch member releasably securing said divider adjacent to said one side wall; and said second means include means responsive to said formation-cutting beginning the second of such cyclical reciprocations for moving said latch member to release said divider for repositioning.

9. The formation-sampling apparatus of claim 8 where- 1n said divider is a iiat strip of a yieldable material of a greater length than the expected length of the rst of such formation samples so that the upper end portion thereof Will extend beyond the upper end of such first sample; andsaid second means further include spring means operative upon the repositioning of said divider for curving sald upper end portion thereof toward said otherside wall to at least partially cover the upper end of such a rst sample.

10. Formation-sampling apparatus for obtaining samples of earth formations traversed by a borehole and cornprising: sample-collecting means adapted for suspension 1l in a borehole and selectively operable from the surface for obtaining multiple samples of earth formations adjacent thereto; a sample receiver dependently coupled to said sample-collecting means and adapted for sequentially admitting such formation samples obtained by said sample-collecting means, said sample receiver having spaced walls adapted for containing such multiple formation samples in a side-by-side relationship; means adapted for segregating such multiple formation samples from one another including a plurality of transverse dividers respectively arranged in said sample receiver for successive movement therein between two of said spaced walls; latch means initially positioning said dividers in a stack adjacent to one of said two spaced walls for directing a first of such formation samples into said sample receiver between said stacked dividers and the other of said two spaced walls, said latch means being progressively movable for successively releasing said dividers from said stack one at a time; biasing means operable upon release of each of said dividers for moving said released dividers toward said other spaced wall; and means responsive to successive operations of said sample-collecting means for progressively moving said latch means to selectively release a single one of said dividers from said stack after each subsequently-obtained formation sample is admitted into said sample receiver to alternately interpose one of said dividers between each adjacent formation sample.

11. The formation-sampling apparatus of claim wherein said sample-collecting means include: formationcutting means adapted to be successively reciprocated longitudinally to obtain elongated formation samples; said dividers are elongated upright members dividing said sample receiver into Vertical compartments respectively adapted to separately contain such elongated formation samples in a generally-upright position therein; and said two spaced walls are opposed side walls of said sample recelver.

12. The formation-sampling apparatus of claim 11 wherein each of said dividers is a yieldable member having an upper end portion adapted to extend above the upper ends of such elongated formation samples contained in said sample receiver; and said biasing means include spring means adapted for respectively deflecting said upper end portion of said dividers, upon their release, further toward said other side wall to at least partially cover the upper ends of such formation samples.

13. The formation-sampling apparatus of claim 11 wherein said dividers respectively have a reduced portion thereon at progressively-higher longitudinal positions; said latch means include a member adapted to initially engage the first of said dividers to be released and be moved longitudinally upwardly into coincidence with said reduced portion thereof to release only said first divider from said stack and, thereafter, successively engage the next of said dividers to be released from said stack and be progressively moved further upwardly into coincidence With said reduced portion thereof to successively release said dividers; and said means for progressively lmoving said latch means include cam means operatively coupling said latch means and said formation-cutting means for progressively moving said latch member upwardly into coincidence with said reduced portions in response to successive reciprocations of said formationcutting means.

14. The formation-sampling apparatus of claim 13 further including: means releasably connecting said cam means to said formation-cutting means for selective actuation thereby during only a .portion of each of said reciprocations of said formation-cutting means and disconnecting said cam means from said formation-cutting means during the remainder of each of said reciprocations.

1S. Formation-sampling apparatus for obtaining samples of earth formations traversed by a borehole comprising: a support adapted for suspension in a borehole; selectively-operable formation-cutting means on said support and adapted for successive reciprocations in relation thereto to obtain multiple elongated samples of earth formations adjacent thereto; a sample receiver dependently coupled below said support and having an yupper opening adapted for admitting such elongated formation samples as they are successively removed and containing such elongated formation samples admitted therein side-byside in upright positions; a plurality of parallel vertical dividers partitioning said sample receiver and respectively movable inwardly therein from an inactive position in a stack along one side of said receiver to an active position laterally spaced from each other for separating such formation samples from one another; and means responsive to repetitive reciprocation of such formationcutting means for successively moving said dividers one at a time into said active positions to consecutively isolate each formation sample admitted into said sample receiver in a predetermined location therein.

16. The formation-sampling apparatus of claim 15 wherein said reciprocation-responsive means include: a retainer member normally engaging the inwardmost one of said stacked dividers for preventing inward movement thereof and adapted for multiple reciprocating movements relative thereto between a lower position and progressively-higher positions; means responsive to movement of said retainer member to each of its said higher positions for consecutively moving the single inwardmost of said dividers still in said stack inwardly to its said active position; cam means coupled to said retainer member and reponsive to sucessive reciprocating movements thereof for consecutively halting said retainer member at each of said higher positions in turn upon each single reciprocation thereof; and coupling means between said retainer member and said formation-cutting means and operative for reciprocating said retainer member a single time upon each reciprocation of said `formation-cutting means.

17. The formation-sampling apparatus of claim 16 wherein said cam means include: a cam follower coupled to said retainer member; and camming means on said receiver for guiding said cam follower and including a plurality of spaced longitudinal channels respectively defining progressively-higher stops to respectively halt said cam follower upon each upward travel therein and a plurality of inclined channels respectively interspersed between adjacent longitudinal channels with the upper end of each inclined channel opening intothe upper portion of the longitudinal channel on one side thereof and the lower end of each inclined channel opening into the lower portion of the longitudinal channel on the other side thereof so as to define an alternating path for said cam follower.

18. The formation-sampling apparatus of claim 17 further including: first abutment means in each of said longitudinal channels for preventing said cam follower from moving downwardly therein without limiting upward movement therein of said cam follower; and second abutment means in each of said inclined channels for preventing said cam follower from moving upwardly therein without limiting downward movement therein of said cam follower.

19. The formation-sampling apparatus of claim 17 wherein said reciprocations of said formation-cutting means are over a greater longitudinal span than the length of said longitudinal channels; and said coupling means between said retainer member and said formation- `cutting means include a first member depending fro-m said formation-cutting means, a second member extending upwardly from said retainer member and coincidentally aligned with said first member, and means adapted for releasably coupling said first and second members only so long as said formation-cutting means are near the lower end of said span and operative upon upward travel of said formation-cutting means to release said first and 13 14 second members once said cam follower engages one 3,405,772 10/1968 Wisenbaker et al. 175-77 of said stops in said longitudinal channels. 3,430,713 3/ 1969 Lanmon 175-78 References Cited DAVID H. BROWN, Primary Examiner UNITED STATES PATENTS 5 Us C1' XR. 2,599,405 6/ 1952 Mennecier 175-78 X 175 311 3,386,522 6/1968 Knupke 175-311 

